RESUMEN
Objective: To validate the correlation between in vitro and in vivo absorption of capsaicin, and study the distribution of capsaicin in tissue after oral administration. Methods: In situ closed loop method was used to measure the absorption of capsaicin from different intestine segments of rats. Concentrations of capsaicin in rat plasma were examined by LC-MS/MS and pharmacokinetic parameters were calculated by the software WinNonlin. Results: The AUC0-240min and Cmax of capsaicin absorbed from colon were higher than those of ileum and jejunum. However, there was no statistic difference. Conclusion: In the primary study, we realized that permeability of capsaicin across the colonic mucosa is remarkably higher than that across jejunal or ileac mucosa in mucosal-to-serosal direction. However, there's no statistical difference for the absorption of capsaicin across different intestinal regions by in situ assay. These results suggest the correlation between in vitro and in situ method is worth further study.